U.S. patent application number 15/339033 was filed with the patent office on 2017-06-15 for light source module.
This patent application is currently assigned to LG ELECTRONICS INC.. The applicant listed for this patent is LG ELECTRONICS INC.. Invention is credited to Jaepyo HONG, Injoong KIM, Jaechan KIM.
Application Number | 20170167713 15/339033 |
Document ID | / |
Family ID | 57211334 |
Filed Date | 2017-06-15 |
United States Patent
Application |
20170167713 |
Kind Code |
A1 |
HONG; Jaepyo ; et
al. |
June 15, 2017 |
LIGHT SOURCE MODULE
Abstract
A light source module includes at least one light source
emitting light, and a body supporting the light source. The body
includes a heat sink supporting the light source on a top surface
thereof, an electrical insulating part provided on the heat sink,
and a plating part provided on the insulating part. The plating
part includes a contact heat dissipation part contacting a portion
of a bottom surface of the light source to receive heat generated
from the light source, and a diffusion heat dissipation part
connected to the contact heat dissipation part for receiving heat
from the contact heat dissipation part to discharge the heat to the
heat sink. Accordingly, quick heat dissipation is performed.
Inventors: |
HONG; Jaepyo; (Seoul,
KR) ; KIM; Jaechan; (Seoul, KR) ; KIM;
Injoong; (Seoul, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LG ELECTRONICS INC. |
Seoul |
|
KR |
|
|
Assignee: |
LG ELECTRONICS INC.
Seoul
KR
|
Family ID: |
57211334 |
Appl. No.: |
15/339033 |
Filed: |
October 31, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H05K 2201/10106
20130101; F21V 29/503 20150115; H05K 2201/0338 20130101; F21V 29/83
20150115; F21V 31/00 20130101; H05K 2203/1355 20130101; H01L 33/64
20130101; H05K 3/107 20130101; F21V 29/713 20150115; F21S 2/005
20130101; H05K 2201/10969 20130101; F21V 3/0625 20180201; H05K
1/0209 20130101; F21V 29/763 20150115; H05K 1/053 20130101; F21V
23/06 20130101; F21Y 2115/10 20160801; F21V 29/74 20150115; H01L
33/647 20130101 |
International
Class: |
F21V 29/71 20060101
F21V029/71; F21V 29/503 20060101 F21V029/503; F21V 23/06 20060101
F21V023/06; F21V 31/00 20060101 F21V031/00; F21V 29/83 20060101
F21V029/83; F21S 2/00 20060101 F21S002/00; F21V 29/76 20060101
F21V029/76 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 14, 2015 |
KR |
10-2015-0178666 |
Jul 21, 2016 |
KR |
10-2016-0092876 |
Claims
1. A light source module comprising: at least one light source
configured to emit light; a heat sink having a surface on which the
light source is supported, the heat sink configured to absorb heat
from the light source and dissipate the heat to the outside; an
electrical insulating part applied to at least one surface of the
heat sink; and a plating part provided on the insulating part, the
plating part comprising: a contact heat dissipation part contacting
a portion of a bottom surface of the light source to receive heat
generated from the light source; and a diffusion heat dissipation
part connected to the contact heat dissipation part to receive heat
from the contact heat dissipation part and discharge the heat to
the heat sink.
2. The light source module according to claim 1, further comprising
a conducting part providing a path for power to be applied to the
light source.
3. The light source module according to claim 2, wherein the
insulating part is provided with a depression part into which the
plating part is provided.
4. The light source module according to claim 2, wherein the
conducting part comprises: at least one light source region on
which the light source is mounted; and a connection region
connected to the light source region.
5. The light source module according to claim 4, wherein the light
source region comprises: a first light source mounting part to
provide a first electric current to the light source; and a second
light source mounting part to provide a second electric current to
the light source.
6. The light source module according to claim 5, wherein the
contact heat dissipation part is disposed between the first light
source mounting part and the second light source mounting part.
7. The light source module according to claim 2, wherein the
conducting part is spaced apart from the diffusion heat dissipation
part.
8. The light source module according to claim 2, wherein the
diffusion heat dissipation part comprises: an inner diffusion heat
dissipation part provided inside the conducting part; and an outer
diffusion heat dissipation part provided outside the conducting
part.
9. The light source module according to claim 8, wherein at least
one side of the contact heat dissipation part is connected to at
least one of the inner diffusion heat dissipation part and the
outer diffusion heat dissipation part.
10. The light source module according to claim 9, wherein the
contact heat dissipation part is a bridge connecting the inner
diffusion heat dissipation part to the outer diffusion heat
dissipation part.
11. The light source module according to claim 1, wherein the heat
sink comprises a heat dissipation fin to absorb heat from the heat
sink and dissipate the heat to the outside.
12. The light source module according to claim 11, further
comprising a lens cover provided at one side of the heat sink and
located over the light source to allow light emitted from the light
source to be transmitted therethrough.
13. A light source module comprising: at least one light source
configured to emit light; a heat sink having a surface on which the
light source is supported, the heat sink configured to absorb heat
from the light source and dissipate the heat to the outside; an
electrical insulating part applied to at least one surface of the
heat sink; and a heat dissipation part provided on the insulating
part, the heat dissipation part comprising: an outer heat
dissipation part disposed adjacent to a corner of the heat sink; an
inner heat dissipation part spaced apart from the outer heat
dissipation part, the inner heat dissipation part being provided
inwardly of the outer heat dissipation part; and a connection heat
dissipation part connecting the outer heat dissipation part to the
inner heat dissipation part, the connection heat dissipation part
having at least one portion contacting a bottom surface of the
light source.
14. The light source module according to claim 13, wherein the
insulating part further comprises a conducting part providing a
path for power to be applied to the light source, the conducting
part being spaced apart from the heat dissipation part, and wherein
the conducting part is located between the outer heat dissipation
part and the inner heat dissipation part.
15. The light source module according to claim 14, wherein the
conducting part is spaced apart from the connection heat
dissipation part.
16. The light source module according to claim 15, wherein the
connection heat dissipation part is provided in plurality, and the
plurality of connection heat dissipation parts are spaced apart
from one another, and wherein the conducting part is disposed
between the connection heat dissipation parts.
17. The light source module according to claim 13, wherein the heat
sink comprises: a heat dissipation fin provided at one side of the
heat sink to absorb heat from the heat sink and dissipate the heat
to the outside; and an air hole opened in a vertical direction of
the heat sink such that air may pass through the air hole in the
heat sink.
18. A light source module comprising: at least one light source
configured to emit light, the at least one light source having at
least one heat dissipation pad provided on a bottom surface of the
light source; a heat sink having a surface on which the light
source is supported, the heat sink configured to absorb heat from
the light source and dissipate the heat to the outside; an
electrical insulating part applied to at least one surface of the
heat sink; and a heat conducting part provided on the insulating
part, the heat conducting part comprising: a contact heat
conducting part at least disposed under the light source to contact
the heat dissipation pad; and a first diffusion heat conducting
part extending at one side of the contact heat conducting part to
discharge heat to at least one surface of the heat sink.
19. The light source module according to claim 18, further
comprising a second diffusion heat conducting part extending at an
other side of the contact heat dissipation part to discharge heat
to at least one other surface of the heat sink.
20. The light source module according to claim 19, wherein the
second diffusion heat conducting part is disposed outwardly of the
first diffusion heat conducting part.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority under 35 U.S.C.
.sctn.119(a) and 35 U.S.C. .sctn.365(b) of Korean Patent
Application Nos. 10-2015-0178666 filed on Dec. 14, 2015 and
10-2016-0092876 filed on Jul. 21, 2016, which are hereby
incorporated by reference in their entirety.
BACKGROUND
[0002] The present disclosure relates to a light source module.
[0003] In general, incandescent bulbs or fluorescent lamps are
frequently used as indoor or outdoor lighting devices. However, the
lifespan of the incandescent bulbs or the fluorescent lamps is
short, and therefore, it is necessary to frequently replace the
incandescent bulbs or the fluorescent lamps with new ones. The
fluorescent lamps can be used for a long period of time as compared
with the incandescent bulbs, but are harmful to the environment. In
addition, the fluorescent lamps are deteriorated over time, and
therefore, the illumination intensity of the fluorescent lamps is
gradually reduced.
[0004] In order to solve these problems, there has been proposed a
light emitting diode (LED) capable of exhibiting excellent
controllability, rapid response speed, high electric/light
conversion efficiency, long lifespan, low power consumption, high
luminance, and emotional lighting. Also, there have been developed
various types of lighting modules and lighting devices employing
the LED.
[0005] The LED is a semiconductor device that coverts electric
energy into light. The LED has advantages of low power consumption,
semi-permanent lifespan, rapid response speed, safety, and
environmental friendly properties as compared with existing light
sources such as fluorescent lamps and incandescent bulbs. For these
reasons, much research has been conducted to replace the existing
light sources with the LED. Furthermore, the LED has been
increasingly used as light sources of lighting devices, such as
various liquid crystal displays, electric bulletin boards, and
streetlights, which are used indoors and outdoors.
[0006] A light emitting device (hereinafter, the light emitting
device is mainly referred to as an LED, but the present disclosure
is not limited thereto) is fabricated in the form of a light source
module for improving assembly convenience and protecting the light
emitting device from external impact and moisture. In the light
source module, a plurality of light emitting devices are integrated
with high density, and hence higher luminance can be realized.
However, heat of a high temperature is generated as a side effect.
Accordingly, much research has been conducted to effectively
dissipate heat from the light emitting module.
[0007] Under the circumstances, Korean Patent Registration No.
10-1472403 filed and registered by the present applicant has
disclosed a light source module for solving the problem of heat
dissipation.
[0008] The light source module above is fabricated by coupling, to
a heat sink, a printed circuit board (PCB) having a plurality of
light emitting devices mounted thereon. However, the heat transfer
property of the printed circuit board is not excellent, and hence
heat is not effectively transferred to the heat sink. Accordingly,
in order to improve the heat dissipation efficiency of the printed
circuit board, a thermal pad is further inserted between the
printed circuit board and the heat sink.
SUMMARY
[0009] Embodiments provide a light source module which can solve a
problem in that heat generated from the light source is not
diffused to the entire heat sink.
[0010] Embodiments also provide a fabrication method for a light
source module, which can solve a problem in that fabrication time
and fabrication cost are excessively required due to a plurality of
fabrication processes caused by coupling a printed circuit board to
a heat sink and inserting a thermal pad between the printed circuit
board and the heat sink, by eliminating the need for a separate
PCB.
[0011] In one embodiment, a light source module includes a light
source and a body supporting the light source.
[0012] The body may include a heat sink discharging heat to the
outside, an insulating part provided on at least one surface of the
heat sink, and a plating part provided on the insulating part.
[0013] The plating part may include a contact heat dissipation part
contacting a portion of a bottom surface of the light source, and a
diffusion heat dissipation part connected to the contact heat
dissipation part, the diffusion heat dissipation part receiving
heat from the contact heat dissipation part to discharge the heat
to the heat sink.
[0014] The plating part may include a conducting part supplying
power to the light source.
[0015] The heat dissipation diffusion part may include an inner
diffusion heat dissipation part and an outer diffusion heat
dissipation part, which are respectively provided inside and
outside the conducting part.
[0016] The outer heat dissipation diffusion part and the inner
diffusion heat dissipation part may be connected to each other by
the contact heat dissipation part. In another embodiment, a method
for fabricating a light source module includes providing a heat
sink, applying an insulating part on at least one surface of the
heat sink, providing a depression part having a metal joint face in
the insulating part, providing the depression part in a heat
dissipation region and a conducting region of a conducting part,
and fastening a light source to the conducting part provided in the
conducting region.
[0017] According to the present disclosure, the light source module
is used in light emitting devices, thereby obtaining much more
advantages in industries.
[0018] According to the present disclosure, the heat dissipation
region for transferring heat generated from the light source to the
heat sink is provided separately from the conducting region for
applying power to the light source, so that the heat generated from
the light source is diffused to the entire heat sink, thereby
improving the heat dissipation efficiency of the light source
module.
[0019] According to the present disclosure, the heat dissipation
regions are provided inside and outside the conducting region,
respectively, so that a heat dissipation area is increased, thereby
maximizing the heat dissipation efficiency.
[0020] According to the present disclosure, the insulating part is
applied to the heat sink by a powder coating technique, a bottom
surface depressed through a laser process is provided in the
insulating part, and the conducting part is provided on the
depressed bottom surface.
[0021] Thus, a process that has inexpensive fabrication cost and is
suitable for mass production can be performed without using any
high-priced printed circuit board and thermal pad. Accordingly, the
light source module can be rapidly fabricated.
[0022] Furthermore, it is possible to obtain various effects that
can be understood through configurations described in the
embodiments.
[0023] The details of one or more embodiments are set forth in the
accompanying drawings and the description below. Other features
will be apparent from the description and drawings, and from the
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a perspective view of a light source module
according to a first embodiment.
[0025] FIG. 2 is an exploded perspective view of the light source
module of FIG. 1.
[0026] FIG. 3 is a front view of the light source module of FIG.
1.
[0027] FIG. 4 is a side view of the light source module of FIG.
1.
[0028] FIG. 5 is a bottom view of the light source module of FIG.
1.
[0029] FIG. 6 is a sectional view taken along line A-A' of FIG.
1.
[0030] FIG. 7 is an enlarged view of a portion at which a light
source is placed in FIG. 1.
[0031] FIGS. 8 to 13 are views sequentially illustrating a
fabrication method of the light source module.
[0032] FIG. 14 is a plan view of the light source module of FIG.
1.
[0033] FIG. 15 is a plan view illustrating a state in which any
protective layer is not provided in the light source module of FIG.
14.
[0034] FIG. 16 is a plan view of a light source module according to
a second embodiment.
[0035] FIG. 17 is a plan view illustrating a state in which any
protective layer is not provided in the light source module of FIG.
16.
[0036] FIG. 18 is a plan view of a light source module according to
a third embodiment.
[0037] FIG. 19 is a plan view illustrating a state in which any
protective layer is not provided in the light source module of FIG.
18.
[0038] FIG. 20 is a sectional view taken along line B-B of the
light source module shown in FIG. 18.
[0039] FIG. 21 is a plan view of a light source module according to
a fourth embodiment.
[0040] FIG. 22 is a plan view illustrating a state in which any
protective layer is not provided in the light source module of FIG.
21.
[0041] FIG. 23 is a view illustrating a state in which a portion of
a heat dissipation region shown in FIG. 21 is modified.
[0042] FIG. 24 is a perspective view of a lighting device including
light source modules according to an embodiment.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0043] Hereinafter, exemplary embodiments will be described in
detail with reference to the accompanying drawings. The technical
objective of embodiments is not limited to the aforementioned
technical problem, and technical problems not mentioned above can
be clearly understood by a person skilled in the art by the
disclosure below.
[0044] FIG. 1 is a perspective view of a light source module
according to an embodiment. FIG. 2 is an exploded perspective view
of the light source module.
[0045] Referring to FIGS. 1 and 2, the light source module 100
according to the embodiment may include at least one light source
11 generating light and a body supporting the light source 11.
[0046] The light source 11 may include all means that generate
light by being supplied with electric energy. For example, the
light source 11 may include a light source in the form of a point
light source. Specifically, the light source 11 may include any one
of a light emitting diode and a laser diode. In the light source
11, a plurality of point light sources emitting light of different
colors may be disposed adjacent to each other such that the colors
are mixed with each other, thereby emitting light of white or
another color.
[0047] The body is provided as a part that allows the light source
11 to perform a physical electrical action, so that the light
source 11 can be stably operated. The body enables heat generated
from the light source 11 to be effectively dissipated. The body is
electrically connected to the light source 11 to supply power to
the light source 11.
[0048] The body may include a heat sink 120. The light source 11
may be fastened to the heat sink 120 through the medium of another
member, or may be directly fastened to the heat sink 120.
Preferably, the light source 11 may be fastened to the heat sink
120 for the purpose of physical coupling such as support of the
weight thereof. However, in order to insulate between the light
source 11 and the heat sink 120, the light source 11 may be
fastened to the heat sink 120 with a predetermined insulating layer
interposed therebetween.
[0049] A mounting part 121 (see FIG. 6) on which the light source
11 is mounted may be provided on one surface of the heat sink 120.
The mounting part 121 allows heat generated from the light source
11 to be rapidly absorbed into the heat sink 120. When a heat
dissipation fin 130 is connected to the other surface of the heat
sink 120, the heat sink 120 may transfer, to the heat dissipation
fin 130, heat generated from the light source 11 and heat generated
by light emitted from the light source 11. It will be apparent that
the heat dissipation fin 130 may rapidly dissipate heat to the
outside. The heat sink 120 may rapidly dissipate heat to the
outside.
[0050] The heat sink 120 may be formed of a metal or resin material
having excellent heat radiation and heat transfer efficiencies, but
the present disclosure is not limited thereto. As an example, the
heat sink 120 may be an alloy made of one or two or more selected
from the group consisting of aluminum (Al), gold (Au), silver (Ag),
copper (Cu), nickel (Ni), tin (Sn), zinc (Zn), tungsten (W), and
iron (Fe). As another example, the heat sink 120 may be formed of
at least one selected from the group consisting of a resin material
such as polyphthalamide (PPA), silicon (Si), aluminum nitride
(AlN), photo sensitive glass (PSG), polyamide9T (PA9T),
syndiotactic polystyrene (SPS), a metal material, sapphire
(Al.sub.2O.sub.3), beryllium oxide (BeO), and ceramic. The heat
sink 120 may be formed through injection molding, etching, etc.,
but the present disclosure is not limited thereto.
[0051] The heat sink 120 has a plate shape, and may be provided
with a quadrangular planar shape. Specifically, the mounting part
121 may be formed by depressing one surface (e.g., an upper
surface) of the heat sink 120. A lens cover 142 may be mounted on
the mounting part 121. The mounting part 121 may be provided with a
waterproof structure with the outside by the lens cover 142. The
light source 11 can be waterproofed by coupling between the
mounting part 121 and the lens cover 142.
[0052] A fastening hole 126 may be formed at an edge of the heat
sink 120. When the light source module 100 is coupled to a lighting
device, a fastening member passes through the fastening hole
126.
[0053] The body may further include the heat dissipation fin 130
and an air hole 122, which improve the heat dissipation efficiency
of the heat sink 120.
[0054] The heat dissipation fin 130 may have a shape in which the
area of the heat dissipation fin 130 contacted with air is
maximized. The heat dissipation fin 130 is transferred with heat of
the heat sink 120 to be heat-exchanged with external air.
Specifically, the heat dissipation fin 130 may be provided in the
shape of a plurality of plates further extending downward from the
other surface (bottom surface) of the heat sink 120. More
specifically, the heat dissipation fin 130 may be disposed in
plurality with a predetermined pitch. In addition, the width of the
heat dissipation fin 130 may be formed in a region in which it is
equal to the width of the heat sink 120 such that heat of the heat
sink 120 can be effectively transferred to the heat dissipation fin
130. The heat dissipation fin 130 may be formed with the heat sink
120 as a single body, or may be fabricated as a separate component
part. Also, the heat dissipation fin 130 may include a material
having excellent heat transfer efficiency, e.g., at least one
selected from the group consisting of aluminum (Al), nickel (Ni),
copper (Cu), silver (Ag), and tin (Sn). Preferably, the heat
dissipation fin 130 may be integrally formed with the heat sink 120
using the same material.
[0055] FIG. 3 is a front view of the light source module. FIG. 4 is
a side view of the light source module.
[0056] Referring to FIGS. 3 and 4, the heat dissipation fin 130 may
be disposed long in the width direction of the heat sink 120. The
heat dissipation fin 130 may be disposed in plurality with a
predetermined pitch in the length direction of the heat sink 120. A
central portion 131 of the heat dissipation fin 130 may be further
depressed toward the heat sink 120 than both end portions 133 of
the heat dissipation fin 130. Since the light sources 11 are
positioned to vertically overlap with both the end portions 133,
respectively, both the end portions 133 of the heat dissipation fin
130 are higher than the central portion 131 of the heat dissipation
fin 130, and thus the contact area of the heat dissipation fin 130
can be increased. The central portion 131 of the heat dissipation
fin 130 may be formed to save fabrication cost.
[0057] The air hole 122 (see FIG. 2) may be formed in the heat sink
120. The air hole 122 may be formed to vertically pass through the
heat sink 120. Specifically, the air hole 122 may be formed to pass
through the heat sink 120 toward the head dissipation fin 130 from
the mounting part 121. The air hole 122 may provide a space in
which air flows. The air hole 122 may be formed long in the length
direction of the heat sink 120 at a central portion of the heat
sink 120. The air hole 122 may communicate with a cover hole 143
(see FIGS. 1 and 2) formed in the lens cover 142 while vertically
overlapping with the cover hole 143.
[0058] The light sources 11 may be positioned at the periphery of
the air hole 122. Specifically, the light sources may be disposed
adjacent to the air hole 122 on the one surface of the heat sink
120, which forms the periphery of the air hole 122. Therefore, the
air hole 122 may be first heated by heat generated from the light
sources 11. The air hole 122 may allow air to be circulated by a
temperature difference between the inside and outside of the air
hole 122. The circulated air may accelerate cooling of the heat
dissipation fin 130 and the heat sink 120. Specifically, the air
hole 122 may be positioned to vertically overlap the central
portion 131 of the heat dissipation fin 130. The light sources 11
may be positioned to respectively overlap both the end portions of
the heat dissipation fin 130.
[0059] FIG. 5 is a bottom view of the light source module.
[0060] Referring to FIG. 5, the light source module 100 may further
include an air guiding part 160 extending downward of the heat sink
120 from the circumference of the air hole 122, the air guiding
part 160 communicating with the air hole 122 to guide air. The air
guiding part 160 may be formed in the shape of a cylinder having a
space therein, and the circumference of the air guiding part 160
may be configured to overlap with the circumference of the air hole
122. That is, the air guiding part 160 may be formed in the shape
of a chimney surrounding the air hole 122. The section of the air
guiding part 160 may be formed in the shape of a rectangle, and
each corner of the rectangle may be curved.
[0061] The air guiding part 160 may be made of a material having
excellent heat transfer efficiency. For example, the air guiding
part 160 may include at least one selected from the group
consisting of aluminum (Al), nickel (Ni), copper (Cu), silver (Ag),
and tin (Sn). Also, the air guiding part 160 may be formed of at
least one selected from the group consisting of a resin material
such as polyphthalamide (PPA), silicon (Si), aluminum nitride
(AlN), photo sensitive glass (PSG), polyamide9T (PA9T),
syndiotactic polystyrene (SPS), a metal material, sapphire
(Al.sub.2O.sub.3), beryllium oxide (BeO), and ceramic.
[0062] The outer surface of the air guiding part 160 is connected
to at least portions of a plurality of heat dissipation fins 130,
so that heat transferred from the light source 11 to the heat
dissipation fin 130 can be transferred to the air guiding part 160.
The air guiding part 160 may further accelerate the air flowing
into the air hole 122. In addition, the heat sink 120 may be
provided with a connector 190 for supplying power to the light
sources 11 and a connector hole 124 (see FIG. 2) through which the
connector 190 passes.
[0063] FIG. 6 is a sectional view taken along line A-A' of FIG.
1.
[0064] Referring to FIG. 6, an electrically insulating layer 20 may
be entirely formed on a surface of the heat sink 120. When the heat
dissipation fin 130 and the air guiding part 160 is formed with the
heat sink 120 as a single body, the insulating layer 20 may also be
formed on surfaces of the heat dissipation fin 130 and the air
guiding part 160. In this case, the heat sink 120, the heat
dissipation fin 130, and the air guiding part 160 may be provided
together by a die-casting technique, and the insulating layer 20
may be then provided.
[0065] The insulating layer 20 may be applied by a powder coating
technique. The powder coating technique may be any one of an
electrostatic spray technique, an electrostatic brush technique,
and a fluidized bed technique. Therefore, the insulating layer 20
may be referred to as a coated insulating layer. Accordingly, a
process can be rapidly and inexpensively performed.
[0066] The insulating layer 20 may insulate between the heat sink
120 and a conductive layer 40 which will be described later. The
conductive layer 40 has electrical conductivity and hence may be
electrically connected to the light source 11. The conductive layer
40 may be a path through which electric current is applied to the
light source 11. Also, the conductive layer 40 may have a function
of rapidly diffusing heat. To this end, the conductive layer 40 may
be made of a metal material. The conductive layer 40 may include at
least one selected from the group consisting of Ag, Au, Cu, and
Ni.
[0067] The light source 11 may be provided as a vertical light
emitting diode including two electrodes formed downwardly. If the
vertical light emitting diode is mounted on the conductive layer
40, separate wire bonding is not required.
[0068] The conductive layer 40 may be provided in a depression part
21 (see FIG. 9) previously formed at a position at which the
conductive layer 40 is to be provided. The depression part 21 is a
region provided by etching the insulating layer 20 through laser
direct structuring (LDS). The depression part 21 may be formed into
a structure in which at least the bottom surface in its internal
region has a rough surface including a metal core.
[0069] The conductive layer 40 may be provided in the depression
part 21 to thereby form circuit patterns interconnecting the light
sources 11 to the connector hole 124. The conductive layer 40 may
be provided by repeatedly performing a plating process at least
once. According to an embodiment, in the conductive layer 40, Cu
and Ni may be sequentially stacked to respectively provide a first
plating layer 41, a second plating layer 42, and a third plating
layer 43, which will be described later. With this configuration,
heat generated by the light sources 11 transfers easily through the
conductive layer 40 and the recess part 21 of the insulating layer
20 to reach the heat sink 120.
[0070] The method of providing the insulating layer 20, the
depression part 21, and the conductive layer 40 may be performed by
forming a conductive film on the insulating layer through
techniques such as sputtering and electrolytic/electroless plating
using a conductive material such as copper and then etching the
conductive film. In this case, the depression part 21 may be
previously provided in the insulating layer 20 so as to prevent a
short circuit, etc. However, more preferably, the LDS may be
performed because fabrication cost is inexpensive, a process can be
rapidly and precisely performed, and mass production can be
achieved using laser equipment.
[0071] The light source module 100 may further include a plurality
of lenses 141 that shield the light sources 11 and refract light
generated from the light sources 11. The lens 141 may diffuse light
generated from the light source 11. The lens 141 may determine the
diffusion angle of light generated from the light source 11
according to its shape. For example, the lens 141 may be molded in
a concave shape around the light source 11. Specifically, the lens
141 may include a material allowing light to be transmitted
therethrough. For example, the lens 141 may be formed of
transparent silicon, epoxy, or another resin material. In addition,
the lens 141 may surround the light source to protect the light
source 11 from external moisture and impact and to isolate the
light source 11 from the outside.
[0072] More specifically, for convenience of assembly, the lens 141
may be provided to the lens cover 142 formed corresponding to the
insulating layer 20. The lens cover 142 may be formed to correspond
to the insulating layer 20 on the top surface of the insulating
layer 20. The lens 141 positioned at the lens cover 142 may be
disposed at a position overlapping the light source 11. The lens
cover 142 may be inserted and mounted into the mounting part 121 to
waterproof the light source 11 from the outside.
[0073] The cover hole 143 communicating with the air hole 122 may
be formed in the lens cover 142. Specifically, the cover hole 143
may be formed to vertically pass through the lens cover 142 at the
center of the lens cover 142.
[0074] The insulating layer 20 may include a material capable of
efficiently reflecting light. In this case, light emitted from the
light source 11 and light reflected from the lens cover 142
including the lens 141 are again reflected to the outside, thereby
further improving the use efficiency of light. Further, light lost
as heat is reduced, thereby achieving high heat dissipation
efficiency.
[0075] FIG. 7 is an enlarged view of a portion at which a light
source is placed.
[0076] Referring to FIG. 7, a metal joint face 22 may be processed
in an inner surface of the depression part 21 (see FIG. 9). In the
metal joint face 22, laser is irradiated onto a plating target
region, so that a surface of the insulating layer 20 can be
processed as a surface having a property suitable for plating. The
metal joint face 22 may be provided with a metal core, or may be
processed as a lattice-shaped trench. The metal joint face 22 may
include at least the bottom surface of the depression part 21.
[0077] The conductive layer 40 may be stacked on the metal joint
face 22. At least one plating layer may be stacked in the
conductive layer 40. For example, the conductive layer 40 may
include the first plating layer 41 made of copper and the second
plating layer 42 made of nickel. The first plating layer 41 may be
stacked to a thickness of 10 to 20 .mu.m, and the second plating
layer 42 may be stacked to a thickness of 5 to 15 .mu.m. In
addition, a third plating layer (not shown) made of gold may be
stacked to a thickness of 0.1 .mu.m or so on the second plating
layer 42. However, the third plating layer (not shown) may cause an
increase in material cost. Therefore, in this embodiment, it will
be described that the third plating layer (not shown) is not
stacked. In addition, the conductive layer 40 is provided by
stacking the first plating layer 41 and the second plating layer on
each other. Therefore, the conductive layer 40 may be referred to
as a "plating part."
[0078] The first plating layer 41 placed at the lowermost side of
the conductive layer 40 serves as an electroconductive functional
layer that can reduce the amount of heat generation by reducing
electrical resistance. To this end, the first plating layer 41 may
be made of copper. In order to ensure sufficient electrical
conductivity, the first plating layer 41 may be formed thickest
among the plating layers. The first plating layer 41 may be made of
a metal having a high electrical conductivity as well as the
copper.
[0079] The second plating layer 42 placed on the first plating
layer 41 serves as a soldering functional layer that improves the
quality of soldering. In order to perform soldering, it is
necessary for a melted solder to be well wettable on the entire
surface of a base material and to be well spread on the surface of
the base material. The second plating layer 42 may be made of
nickel as a metal for ensuring characteristics of the
soldering.
[0080] A bonding layer 50 may be provided on the conductive layer
40. The light source 11 may be placed on the bonding layer 50. In
other words, the bonding layer 50 may be previously provided at a
portion at which the light source 11 is placed. The bonding layer
50 may include a low-temperature solder paste with which soldering
can be performed at a low temperature. For example, the bonding
layer 50 may include OM525. The bonding layer 50 may be provided by
allowing the low-temperature solder paste to pass through a reflow
machine in a state in which the light source 11 is disposed on the
low-temperature solder paste. The soldering is performed at the low
temperature, so that it is possible to prevent separation between
the heat sink 120 and the insulating layer 20 and separation
between the insulating layer 20 and the conductive layer 40.
[0081] A protective layer 60 may be provided on a portion of the
conductive layer 40. The protective layer 60 may be provided in a
region except the conductive layer 40 on which the bonding layer 50
is provided. In other words, the protective layer 60 may be
provided in a region except the conductive layer 40 at the portion
at which the light source 11 is to be mounted on the insulating
layer 20 or the conductive layer 40.
[0082] The protective layer 60 can prevent the conductive layer 40
from being oxidized. Also, the protective layer 60 can prevent a
foreign substance, a water drop, or the like from penetrating into
the conductive layer 40. Also, the protective layer 60 can protect
the conductive layer 40 from external impact.
[0083] FIGS. 8 to 13 are views sequentially illustrating a
fabrication method of the light source module.
[0084] First, referring to FIG. 8, the insulating layer 20 may be
provided to a body fabricated by, for example, a die-casting
technique.
[0085] The insulating layer 20 may be applied by a powder coating
technique. The powder coating technique may be any one of an
electrostatic spray technique, an electrostatic brush technique,
and a fluidized bed technique. Therefore, the insulating layer 20
may be referred to as a coated insulating layer.
[0086] The thickness of the coated insulating layer may be 60 to 80
.mu.m. However, the thickness is not limited thereto, and may be
selected to have various dimensions according to insulation
performance, heat dissipation performance, and process variables.
In an embodiment, a condition may be found in which, when the light
source 11 is a light emitting diode and is connected to a
commercial power source, the insulation and heat dissipation of the
insulating layer 20 can be ensured, and the providing of the
insulating layer 20 can be performed through an inexpensive
process.
[0087] The LDS may be applied to the insulating layer 20 such that
the conductive layer 40 is plated on at least one portion of the
surface of the insulating layer 20.
[0088] The LDS is a process performed before a plating process, and
refers to a process of irradiating laser onto a plating target
region of the surface of the insulating layer 20, so that a plating
target region of the surface of a resin molded article is reformed
to have a property suitable for plating. To this end, the
insulating layer 20 may contain a "core generating agent for LDS
(hereinafter, simply referred to as a `core generating agent`)"
capable of forming a metal core by means of laser, or may have a
predetermined pattern formed therein such that a plating layer is
provided at the inner surface of the depression part 21.
[0089] First, a case where the insulating layer 20 contains a core
generating agent will be described.
[0090] A core generating agent may be contained in the resin molded
article providing the insulating layer 20. If laser is irradiated
onto the core generating agent, a metal core may be generated as
the core generating agent is decomposed. In addition, the plating
target region onto which the laser is irradiated may have a surface
roughness. The plating target region reformed by the laser can be
suitable for plating due to the metal core and the surface
roughness. The metal core may mean a core with which a metal is
joined in a subsequent plating process.
[0091] The core generating agent may include a metal oxide having a
spinel, a heavy metal composite oxide spinel such as copper
chromium oxide spinel, a copper salt such as copper hydroxide
phosphate, copper phosphate, copper sulfate, or cuprous
thiocyanate, and the like. A polyester-based resin may be used as
the resin molded article. Since the polyester-based resin has
better adhesion with a metal, it is possible to prevent separation
between the heat sink 120 and the insulating layer 20 and
separation between the insulating layer 20 and the conductive layer
40, which may occur in a bonding process of the light source 11 as
a subsequent process.
[0092] A case where a predetermined pattern is formed in the inner
surface of the depression part 21 will be described in detail.
Although the resin molded article does not contain the core
generating agent, the conductive layer 40 may be provided by
forming a trench line with a predetermined pattern arrangement in
the plating target region. The plating process may be performed on
the trench line by effectively promote the joining of a metal with
the plating target region on the surface of the resin molded
article. The trench line may be provided with at least two kinds of
trenches intersecting each other.
[0093] The forming of the trench line with the predetermined
pattern arrangement may be performed by irradiating laser onto the
plating target region of the surface of the resin molded
article.
[0094] FIG. 9 is a view illustrating that the depression part is
provided in the insulating layer.
[0095] Referring to FIG. 9, laser may be used as a means for
providing the depression part 21 in the insulating layer 20. A
medium providing the laser may include, for example, yttrium
aluminum garnet (YAG), yttrium orthovanadate (YVO4), ytterbium
(YB), CO.sub.2, etc. The wavelength of the laser may be, for
example, 532 nm, 1064 nm, 1090 nm, 9.3 .mu.m, 10.6 .mu.m, etc.
[0096] An algorithm in which processing is performed by recognizing
a three-dimensional (3D) shape may be used when the processing is
performed using the laser. For example, a method may be applied in
which the processing height of the laser is controlled by
recognizing a 3D-shaped component part using a 3D recognition
program and separating the component part into several levels for
every height. Outer line processing may be additionally performed
to achieve plating uniformity between a non-processing surface and
a plating surface formed by processing the metal joint face 22
using laser. The output value of the laser may be, for example,
about 2 W to 30 W.
[0097] The metal joint face 22 processed by the laser has the metal
core, the rough surface, and the trench, so that the conductive
layer 40 can be plated in a subsequent process.
[0098] FIG. 10 is a view illustrating that the conductive layer is
provided in the depression part.
[0099] Referring to FIG. 10, the conductive layer 40 may be
provided by plating a metal on the metal joint face 22 using an
electroless process. It will be apparent that another plating
process may be performed. The conductive layer 40 may be copper,
nickel, gold, silver, or a combination thereof. The conductive
layer 40 may be a single-layered or stacked structure. In the
stacked structure, layers may be the same metal or different
metals. In this embodiment, it is illustrated that copper and
nickel are sequentially stacked.
[0100] As an embodiment, a case where the first plating layer 41
made of copper is provided will be described in detail. The heat
sink 120 providing the metal joint face 22 is immersed in an
electroless copper plating solution. In this case, the heat
dissipation fin 130 and the air guiding part 160 may be immersed
together with the heat sink 120.
[0101] For example, an aqueous plating solution for electroless
copper may contain about 55 ml to about 65 ml of a copper dry
bathing/supplementing agent, about 55 ml to about 65 ml of an
alkaline supplementing agent, about 15 ml to about 20 ml of a
complexing agent, about 0.1 ml to about 0.2 ml of a stabilizing
agent, and about 8 ml to about 10 ml of formaldehyde, based on
deionized water.
[0102] The copper dry bathing/supplementing agent may contain, for
example, about 6 parts by weight to about 12 parts by weight of
copper sulfate, about 1 part by weight to about 1.5 parts by weight
of polyethylene glycol, about 0.01 part by weight to about 0.02
part of weight of the stabilizing agent, and about 78 parts by
weight to about 80 parts by weight of water.
[0103] The alkaline supplementing agent may contain, for example,
about 40 parts by weight to about 50 parts by weight of sodium
hydroxide, about 0.01 part by weight to about 0.02 part by weight
of the stabilizing agent, and about 50 parts by weight to about 60
parts by weight of the water.
[0104] The complexing agent may contain, for example, about 49
parts by weight to about 50 parts by weight of the sodium
hydroxide, about 0.01 part by weight to about 0.02 part by weight
of the stabilizing agent, and about 50 parts by weight to about 51
parts by weight of the water.
[0105] The stabilizing agent may contain, for example, about 0.2
part by weight to about 0.3 part by weight of potassium
selenocyanate, about 5 parts by weight to about 6 parts by weight
of potassium cyanide, about 0.3 part by weight to about 0.4 part by
weight of the sodium hydroxide, and about 92 parts by weight to
about 93 parts by weight of the water.
[0106] For example, in order to provide the first plating layer 41
made of copper, a resin molded article provided with a catalyst may
be immersed at a deposition speed of about 0.5 to about 0.7
.mu.m/10 min in the electroless copper solution at about 41.degree.
C. to about 55.degree. C. and then washed by water.
[0107] The conductive layer 40 may be stacked up to a range
exceeding the depth of the depression part 21. Accordingly, the
resistance of the conductive layer 40 can be reduced, and the heat
conduction amount of the conductive layer 40 can be increased,
thereby improving heat dissipation performance. It will be apparent
that the present disclosure is not limited to the above-described
configuration.
[0108] FIG. 11 is a view illustrating that the protective layer is
provided.
[0109] Referring to FIG. 11, the protective layer 60 may be applied
on the conductive layer 40. Also, the protective layer 60 may be
further applied on the insulating layer 20. In other words, the
protective layer 60 may be applied on the entire upper surface of
the heat sink 20.
[0110] However, the protective layer 60 may be provided to open a
light source region 200 (see FIG. 14) in which the light source 11
is mounted. Here, the light source region 200 may be referred to as
a partial region of the conductive layer 40, in which the light
source 11 is mounted.
[0111] In the method of providing the protective layer 60 to open
the light source region 200, the protective layer 60 is provided,
and an etching process is then performed such that the light source
region 200 is exposed. Alternatively, a thin film is placed in the
light source 200, the protective layer 60 is provided, and a
process of removing the thin film is then performed.
[0112] The protective layer 60 may include an insulating material.
For example, the protective layer 60 may include a solder resist,
an epoxy material, a nano insulating coating material, a flexible
composite insulating material, an organic material, an insulating
permanent coating material, a polycarbonate material, a resin
material, etc.
[0113] In this embodiment, it is described that the protective
layer 60 is formed of a solder resist including a permanent
(petroleum) compound, an epoxy resin, a phenol-based hardener, a
hardening accelerator, and the like.
[0114] A process of stacking the protective layer 40 will be
described. The protective layer 60 may be applied on the entire
surface of the conductive layer 40 and the insulating layer 20.
[0115] A technique for applying the protective layer 60 may include
a silk screen printing technique, a photo solder resist (PSR)
printing technique, etc. For example, the protective layer 60 may
be applied by performing a process of applying an IR ink
corresponding to a thermosetting resin composition and then
heat-drying and curing the IR ink.
[0116] Also, the protective layer 60 may be applied by performing a
process of applying a UV ink corresponding to an ultraviolet
setting resin composition and then drying and curing the UV ink
through irradiation of ultraviolet light.
[0117] Also, the protective layer 60 may be applied by entirely
applying a PSR ink and then performing processes including
exposure, developing, UV drying (curing), and the like, in addition
to a process of heat-drying the ink.
[0118] After the protective layer 60 is applied, an etching process
may be performed to remove the protective layer 60 applied on the
light source region 200. For example, the etching process may be at
least one of a plasma etching process, a wet etching process, and a
reactive ion etching process. If the etching process is performed,
the protective layer 60 may be provided such that the light source
region 200 is opened.
[0119] FIG. 12 is a view illustrating that the bonding layer is
provided.
[0120] Referring to FIG. 12, the bonding layer 50 may be provided
in the light source region 200 (see FIG. 14). In other words, the
bonding layer 50 may be provided on the conductive layer 40 on
which the light source 11 is to be mounted. The bonding layer 50
may electrically connect the light source 11 and the conductive
layer 40 to each other.
[0121] The bonding layer 50 may be provided by applying a
low-temperature solder paste on the conductive layer 40 on which
the light source 11 is to be mounted, mounting the light source 11
at a position at which the electrodes of the light source 11 are
aligned on the low-temperature solder paste, and then allowing the
low-temperature solder paste to pass through a reflow machine. In
the reflow process, an unnecessary portion is removed from the
low-temperature solder paste, and a conductive element remains, so
that the conductive layer 40 and the light source 11 can be
electrically connected to each other.
[0122] The low-temperature solder paste may include OM525 available
at about 160.degree. C. Since a relatively low temperature
atmosphere is formed in the reflow process, it is possible to
prevent separation between the insulating layer 20 and the heat
sink 120 and separation between the conductive layer 40 and the
insulating layer 20.
[0123] FIG. 13 is a view illustrating that the lens is further
provided over the light source.
[0124] Referring to FIG. 13, the lens 141 may be provided over the
light source 11. The lens 141 may shield the light source 11. Also,
the lens 141 may refract and diffuse light generated from the light
source 11.
[0125] The lens 141 may determine the diffusion angle of light
generated from the light source 11 according to its shape. For
example, the lens 141 may be molded in a concave shape around the
light source 11. Specifically, the lens 141 may include a material
allowing light to be transmitted therethrough. For example, the
lens 141 may be formed of transparent silicon, epoxy, or another
resin material. In addition, the lens 141 may surround the light
source to protect the light source 11 from external moisture and
impact and to isolate the light source 11 from the outside.
[0126] More specifically, for convenience of assembly, the lens 141
may be disposed at the lens cover 142 formed corresponding to the
insulating layer 20. Also, the lens 141 may be disposed at the lens
cover 142 formed corresponding to the protective layer 60 provided
on the insulating layer 20 or the conductive layer 40.
[0127] The lens cover 142 may be formed to correspond to the
insulating layer 20 on the top surface of the insulating layer 20.
The lens 141 positioned at the lens cover 142 may be disposed at a
position overlapping the light source 11.
[0128] The lens cover 142 may be inserted in the mounting part 121
to waterproof the light source 11 from the outside. Also, the lens
cover 142 may be fastened to the heat sink 120 through a fastening
member to waterproof the light source 11 from the outside.
[0129] FIG. 14 is a plan view of the light source module of FIG. 1,
which illustrates a state in which the lens cover is omitted. FIG.
15 is a plan view illustrating a state in which any protective
layer is not provided in the light source module of FIG. 14.
[0130] Referring to FIGS. 14 and 15, the mounting part 121 (see
FIG. 6) on which the light source 11 is mounted may be formed on
the top surface of the heat sink 120. The mounting part 121 may be
provided by being depressed in the direction of the bottom surface
of the heat sink 200.
[0131] The mounting part 121 may be provided with the insulating
layer 20 having electrically insulating properties, the conductive
layer 40 provided in the depression part 21 (see FIG. 9) of the
insulating layer 20, and the protective layer 60 protecting the
insulating layer 20 and the conductive layer 40. In other words,
the protective layer 60 may be provided on the entire surface of
the insulating layer 20 and the conductive layer 40, which are
provided in the mounting part 121. Also, the protective layer 60
may be provided on only a portion of the conductive layer 40.
However, the present disclosure is not limited to the
above-described configuration. In this embodiment, it will be
described that the protective layer 60 is provided on the
conductive layer 40 and the insulating layer 20.
[0132] The conductive layer 40 may include the light source region
200 in which the light source 11 is mounted and a connection region
(see 220 of FIG. 15) provided to supply electric current to the
light source 11. The light source region 200 may be referred to as
a region in which the light source 11 is placed on the conductive
layer 40.
[0133] The light source region 200 may be provided to face the
light source 11. Specifically, the bottom surface of the light
source 11 may include a positive electrode face 12 to which a
positive electric current is applied, a negative electrode face 13
to which a negative electric current is applied, and a heat
dissipation face 14 that transfers heat generated from the light
source 11. The faces may be formed to be spaced apart from each
other. Therefore, the light source region 200 may include a first
light source mounting part 201 facing the positive electrode face
12 and a second light source mounting part 202 facing the negative
electrode face 13. Also, the light source region 200 may include a
third light source mounting part 203 facing the heat dissipation
face 14. The third light source mounting part 203 may be not
provided. However, the present disclosure is not limited to the
above-described configuration. In this embodiment, it will be
described that the third light source mounting part 203 is
provided.
[0134] The first light source mounting part 201 and the second
light source mounting part 202 may apply electric current to the
light source 11. Specifically, if a "positive electric current" is
applied to the first light source mounting part 201, a "negative
electric current" may be applied to the second light source
mounting part 202. The third light source mounting part 203 may
transfer heat generated from the light source 11 to the heat sink
120.
[0135] The connection region 220 may connect different light
sources 11 to each other. Also, the connection region 220 may
supply, to the light source 11, power applied from a power source
part (not shown). Therefore, the connection region 220 may be
provided as a straight conducting path connected to supply electric
current to the light source 11. In addition, the connection region
220 may be provided in a pattern repeated in a certain shape, a
curved line, a shape having different thicknesses, or the like.
However, the present disclosure is not limited to the
above-described configuration. In this embodiment, it will be
described that the connection region 220 is provided as a straight
conducting path through which electric current is applied to the
light source 11.
[0136] The protective layer 60 may be provided on the conductive
layer 40 and the insulating layer 20. However, the light source
region 200 may be opened such that the light source 11 is mounted
therein. The protective layer 60 may be provided on the insulating
layer 20 and a portion of the conductive layer except the light
source region 200. Also, the protective layer 60 may be provided in
only the connection region 220. However, the present disclosure is
not limited to the above-described configuration. In this
embodiment, it will be described that the protective layer 60 is
provided on the conductive layer 40 and the insulating layer 20,
and the light source region 200 is opened such that the light
source 11 is mounted therein.
[0137] The protective layer 60 may include an insulating material.
For example, the protective layer 60 may include a silicon
material, a solder resist, an epoxy material, a nano insulating
coating material, a flexible composite insulating material, an
organic material, an insulating permanent coating material, a
polycarbonate material, a resin material, etc. However, in this
embodiment, it will be described that the protective layer 60 is a
solder resist.
[0138] The solder resist may include a permanent (petroleum)
compound, an epoxy resin, a phenol-based hardener, and a hardening
accelerator.
[0139] The protective layer 60 may protect the conductive layer 40
from the bonding layer 50 (see FIG. 7). Specifically, the
protective layer 60 may be provided such that only the light source
region 200 is opened. According to the above-described
configuration, the protective layer 60 can guide a region in which
the bonding layer 50 may be melted and flow down when the light
source 11 and the conductive layer 40 are coupled to each other.
Thus, it is possible to prevent malfunction of the light source 11
as the bonding layer 50 flows down on the conductive layer 40.
Further, it is possible to provide a neat external appearance.
[0140] The protective layer 60 can protect the conductive layer 40
from a foreign substance, a water drop, an insect, etc.,
penetrating from the outside. Specifically, if high-temperature
heat is generated from the light source 11, thermal deformation of
the conductive layer 40 or chemical reaction of a conductive
material may be accelerated. For example, when the conductive layer
40 is made of copper, the copper is oxidized when it comes in
contact with water or air. Therefore, the copper may be corroded or
discolored. When the conductive layer 40 is made of nickel, a
harmful material may be generated. In addition, the conductive
layer 40 may cause a problem of corrosion or overload through a
foreign substance or pollutant penetrating from the outside.
Accordingly, if the protective layer 60 is provided on the
conductive layer 40, the conductive layer 40 can be protected, and
thus it is possible to prevent a problem caused by corrosion.
Further, the lifespan of products can be increased by preventing
overload.
[0141] The second embodiment is characterized in that any specific
portion is modified in the first embodiment. Therefore, in the
second embodiment, description of the first embodiment will be
identically applied to portions identical to those of the first
embodiment.
[0142] FIG. 16 is a plan view of a light source module according to
a second embodiment. FIG. 17 is a plan view illustrating a state in
which any protective layer is not provided in the light source
module of FIG. 16.
[0143] Referring to FIGS. 16 and 17, the insulating layer 20 having
electrically insulating properties and the conductive layer 40
capable of supplying power to the light source 11 may be provided
on the heat sink 120. That is, the mounting part 121 (see FIG. 6)
is not provided in the heat sink 120, and the insulating layer 20
and the conductive layer 40 may be directly provided on the heat
sink 120. However, the present disclosure is not limited to the
above-described configuration. According to the above-described
configuration, the thickness of the heat sink 120 is further
decreased, thereby improving heat dissipation efficiency.
[0144] The conductive layer 40 may be provided in the depression
part 21 (FIG. 9) formed in the insulating layer 20. The conductive
layer 40 may include a light source region 300 in which the light
source 11 is mounted, a connection region 320 through which power
is applied to the light source 11, and a heat dissipation region
350 formed to be spaced apart from the connection region 320.
[0145] The heat dissipation region 350 may transfer heat generated
from the light source 11 to the heat sink 120. Also, the heat
dissipation region 350 may diffuse heat transferred from the light
source 11 to the heat sink 120. Also, the heat dissipation region
350 may be provided such that the light source region 300 and the
connection region 320 are not electrically connected to each other.
Also, the heat dissipation region 350 may be provided on the
insulating layer 20 except regions in which the light source region
300 and the connection region 320 are provided. However, the
present disclosure is not limited to the above-described
configuration. In a functional aspect, the heat dissipation region
350 diffuses and dissipates the heat transferred from the light
source 11. Therefore, the heat dissipation region 350 may be
referred to as a "diffusion part" or "heat dissipation part." In
addition, the heat dissipation region 350 may also be referred to
as a "heat conducting part" in a heat transfer aspect.
[0146] The heat dissipation region 350 may include an inner heat
dissipation region 351 provided inside the light source region 300
and the connection region 320, and an outer heat dissipation region
352 provided outside the light source region 300 and the connection
region 320.
[0147] The light source region 300 may include a first light source
mounting part 301 applying a positive electric current to the light
source 11, a second light source mounting part 302 applying a
negative electric current to the light source 11, and a third light
source mounting part 303 transferring heat generated from the light
source 11 to the heat sink 120.
[0148] The third light source mounting part 303 may be provided to
be spaced apart from the first light source mounting part 301 and
the second light source mounting part 302. In addition, the third
light source mounting part 303 may be connected to the heat
dissipation region 350. In other words, the third light source
mounting part 303 may be understood as a bridge connecting the
inner heat dissipation region 351 and the outer heat dissipation
region 352 to each other. That is, the heat dissipation region 350
may be provided as a single body.
[0149] According to the above-described configuration, the heat
dissipation region 350 can more efficiently transfer heat generated
from the light source 11 to the heat sink 120.
[0150] The conductive layer 60 may be provided on the insulating
layer 20 and the conductive layer 40. However, the protective layer
60 may be provided such that the light source region 300 having the
light source 11 mounted therein is opened. The protective layer may
be provided on only a portion of the conductive layer 40. However,
the present disclosure is not limited to the above-described
configuration. In this embodiment, it will be described that the
protective layer 60 is provided on the insulating layer 20 and the
conductive layer 40, and only the light source region 300 is
opened.
[0151] The protective layer 60 may include a reflective material.
Specifically, the protective layer 60 may be disposed relatively
downward of the light source 11. Thus, the protective layer 60 can
serve as a reflective layer reflecting light emitted from the light
source 11. For example, the reflective material may include a white
or silver material, a reflective silicon material, a silicon white
reflector material, a silicon white reflective material, etc. The
reflective material may be provided as a material that reflects
high-temperature heat generated from the light source 11 and has
high optical stability.
[0152] According to the above-described configuration, the
protective layer 60 can have excellent reflectivity with respect to
light emitted from the light source 11. That is, it is possible to
obtain high optical efficiency through the protective layer 60.
[0153] Meanwhile, the protective layer 60 may become a medium on
which characters 400 can be printed. Specifically, the characters
400 can be easily provided to the light source module 100 through
an etching process the top surface of the protective layer 60 or a
printing process of applying an inert ink on the top surface of the
protective layer 60. That is, the protective layer 60 becomes the
medium capable of providing the characters 400, so that it is
possible to prevent damage of the insulating layer 20 or the
conductive layer 40.
[0154] The third embodiment is characterized in that any specific
portion is modified in the first embodiment. Therefore, in the
third embodiment, description of the first embodiment will be
identically applied to portions identical to those of the first
embodiment.
[0155] FIG. 18 is a plan view of a light source module according to
a third embodiment, which illustrates a state in which the lens
cover is omitted. FIG. 19 is a plan view illustrating a state in
which any protective layer is not provided in the light source
module of FIG. 18. FIG. 20 is a sectional view taken along line B-B
of the light source module shown in FIG. 18.
[0156] Referring to FIGS. 18 to 20, the mounting part 121 (see FIG.
6) on which the light sources 11 are mounted may be formed on the
top surface of the heat sink 120. The mounting part 121 may be
provided by being depressed in the direction of the bottom surface
of the heat sink 200.
[0157] The mounting part 121 may be provided with the insulating
layer 20 having electrically insulating properties, the conductive
layer 20 provided in the depression part 21 (see FIG. 9) of the
insulating layer 20, and the protective layer 60 protecting the
insulating layer 20 and the conductive layer 40.
[0158] The protective layer 60 may be provided on the entire
surface of the insulating layer 20 and the conductive layer 40,
which are provided in the mounting part 121. Also, the protective
layer 60 may be provided on only a portion of the conductive layer
40. However, the present disclosure is not limited to the
above-described configuration.
[0159] The conductive layer 40 may include the light source region
200 in which the light source 11 is mounted and a connection region
(see 220 of FIG. 19) provided to supply electric current to the
light source 11. One side and the other side of the light source
region 200 may be connected to the connection region 220.
[0160] That is, the light source region 200 may be understood as a
region in which the light source 11 is placed on the conductive
layer 40. In another aspect, the light source region 200 may also
be understood as a portion that is located between a plurality of
connection regions 220 spaced apart from each other to contact one
side and the other side of the light source 11.
[0161] The light source region 200 is indicated by black so as to
be clearly distinguished from the connection region 220.
[0162] The light source region 200 may be provided to face the
light source 11. Specifically, a first electrode pad 12 and a
second electrode pad 13, to which electric current is applied, may
be provided on the bottom surface of the light source 11. In
addition, a heat dissipation pad 14 for transferring heat generated
from the light source 11 may further provided on the bottom surface
of the light source 11. The pads 12, 13, and 14 may be provided to
be spaced apart from one another on the bottom surface of the light
source 11. The pads 12, 13, and 14 provided on the bottom surface
of the light source 11 may be made of copper having excellent
thermal conductivity and electrical conductivity to heat or
electric current. However, the present disclosure is not limited
thereto.
[0163] The light source region 200 may include a first light source
mounting part 201 facing the first electrode pad 12 and a second
light source mounting part 202 facing the second electrode pad 13.
The light source region 200 may further include a third light
source mounting part 203 facing the heat dissipation pad 14.
[0164] The third light source mounting part 203 and the heat
dissipation pad 14 may not be provided. However, in order to more
quickly dissipate the heat generated from the light source 11, the
third light source mounting part 203 and the heat dissipation pad
14 are preferably provided.
[0165] The first light source mounting part 201 and the second
light source mounting part 202 may apply power to the light source
11. Specifically, wires 191 for supplying power to the light source
11 may be disposed to pass through the connector hole 124. Also,
the wire 191 may contact a portion of the conductive layer 40,
i.e., a portion of the connection region 220 to apply power to the
light source 11. In this case, the protective layer 60 may not be
provided on the portion of the conductive layer 40, connected to
the wire 124.
[0166] The wire 191 may contact the conductive layer 40 through a
solder, a conductive bonding agent, etc. Alternatively, a
connection part may be provided to the portion of the conductive
layer 40 such that the wire 191 is inserted into the connection
terminal. However, the present disclosure is not limited
thereto.
[0167] If power is applied to the connection region 220, the power
may be applied to the light source 11 mounted on the light source
region 200. For example, if a "positive electric current" is
applied to the first light source mounting part 201 and a "negative
electric current" is applied to the second light source mounting
part 202, the light source 11 may emit light.
[0168] That is, the connection region 220 and the light source
region 200 may be referred to as "conducting regions," "conducting
parts." At this time, since the third light source mounting part
203 of the light source region 200 does not apply power to the
light source 11, the third light source mounting part 203 is not
referred to as a "conducting region" or "conducting part."
[0169] The connection region 220 may connect different light
sources 11 to each other. Also, the connection region 220 may
supply the power applied from the wire 191 to the different light
sources 11.
[0170] Meanwhile, the bonding layer 50 (see FIG. 20) may be
provided on the conductive layer 40 of the light source region 200.
In addition, the protective layer 60 may be provided in a region
except the light source region 200.
[0171] Hereinafter, the state in which the light source 11 is
mounted on the conductive layer 40 will be described in detail with
reference to FIG. 20.
[0172] The light source 11 may be connected to the conductive layer
40 by the bonding layer 50. In this case, the light source 11 may
be mounted on a region corresponding to the light source region 200
in the conductive layer 40. The light source region 200 may be
provided in plurality depending on the number of light sources 11.
In addition, different light source regions 200 are connected to
each other by the connection region 220 to form one closed
circuit.
[0173] The light source region 200 may include the first light
source mounting part 201 contacting the first electrode pad 12 of
the light source 11 and the second light source mounting part 202
contacting the second electrode pad 13 of the light source 11. The
light source region 200 may further include the third light source
mounting part 203 contacting the heat dissipation pad 14 for
dissipating heat generated from the light source 11. Here, the
first light source mounting part 201 and the second light source
mounting part 202 may be understood as conductive layers 40 for
conducting power. The third light source mounting part 203 may be
understood as a conductive layer 40 for dissipating heat.
[0174] The first electrode pad 12 of the light source 11 may
contact the first light source mounting part 201. The second
electrode pad 13 of the light source 11 may contact the second
light source mounting part 202. The heat dissipation pad 14 of the
light source 11 may contact the third light source mounting part
203. In this case, the third light source mounting part 203 is a
conductive layer contacting the heat dissipation pad 14 to
dissipate heat, and may be referred to as a "contact heat
dissipation part."
[0175] The conductive layer 40 of the light source region 200 may
be formed by stacking a first conductive layer 41 and a second
conductive layer 42 on the insulating layer 20.
[0176] The first light source mounting part 201, the second light
source mounting part 202, and the third light source mounting part
203 may be disposed to be spaced apart from one another. This is
provided for the purpose of preventing a problem occurring as the
first light source mounting part 201, the second light source
mounting part 202, and the third light source mounting part 203
contact one another.
[0177] Meanwhile, the third light source mounting part 203 may be
provided in a single layer instead of multiple layers such as the
first conductive layer 41 and the second conductive layer 42. Also,
the third light source mounting part 203 may be provided to
directly contact the heat sink 120 by passing through the
insulating layer 20.
[0178] According to the above-described configuration, the heat
generated from the light source 11 is directly transferred onto the
heat sink 120, so that the heat dissipation performance can be
further improved.
[0179] However, a process of allowing the third light source
mounting part 203 to contact the heat sink 120 by passing through
the insulating layer 20 is complicated, and fabrication cost may be
increased. In addition, a lifting phenomenon may occur in the
insulating layer 20 contacting the first light source mounting part
201 and the second light source mounting part 202 in a process of
allowing the third light source mounting part 203 to additionally
pass through the insulating layer 20 to be provided adjacent to the
heat sink 20.
[0180] Therefore, in this embodiment, it is described that the
third light source mounting part 203 is fabricated by the same
fabrication method as the first light source mounting part 201 and
the second light source mounting part 202.
[0181] The power transferred to the connection region 220 through
the wire 191 may be applied to the first electrode pad 12 of the
light source 11 contacting the first light source mounting part 201
of the light source region 200 and the second electrode pad 13 of
the light source 11 contacting the second light source mounting
part 202 of the light source region 200. If the power is applied to
the first and second electrode pads 12 and 13, the light source 11
may emit light.
[0182] The heat generated from the light source 11 may be
transferred to the third light source mounting part 203 through the
heat dissipation pad 14 of the light source 11. The heat
transferred to the third light source mounting part 203 may be
transferred to the insulating layer 20, the heat sink 120, and the
heat dissipation fin 130 to be dissipated to the outside. Here, the
third light source mounting part 203 may be referred to as a "light
source heat dissipation region" or "light source heat dissipation
part" for dissipating heat generated from the light source 11.
[0183] According to the above-described configuration, the heat
generated from the light source 11 is quickly transferred to the
heat sink 120, so that the heat dissipation efficiency can be
improved.
[0184] The fourth embodiment is characterized in that any specific
portion is modified in the second and third embodiments. Therefore,
in the fourth embodiment, descriptions of the second and third
embodiments will be identically applied to portions identical to
those of the second and third embodiments.
[0185] FIG. 21 is a plan view of a light source module according to
a fourth embodiment, which illustrates a state in which the lens
cover is omitted. FIG. 22 is a plan view illustrating a state in
which any protective layer is not provided in the light source
module of FIG. 21. FIG. 23 is a view illustrating a state in which
a portion of a heat dissipation region shown in FIG. 21 is
modified.
[0186] Referring to FIGS. 21 to 23, a plurality of conductive
layers 40 may be provided on the mounting part 121 of the heat sink
121. In addition, a protective layer 60 may be provided on the
mounting part 121. That is, the protective layer 60 may cover the
plurality of conductive layers 40 provided on the mounting part
121.
[0187] However, the protective layer 60 is provided to be opened on
the conductive layer 40 of a region in which a light source 11 is
mounted. In addition, the protective layer 60 is provided to be
opened at a portion at which a wire 191 for supply power to the
light source 11 contacts the conductive layer 40. This is a space
for allowing the light source 11 to contact the conductive layer
40, and the space is provided for the purpose of supplying power by
allowing the light source 11 to contact the conductive layer 40.
However, the present disclosure is not limited thereto.
[0188] The conductive layer 40 may include a light source region
300 on which the light source 11 is mounted, a connection region
320 for applying power to the light source, and a heat dissipation
region 350 formed to be spaced apart from the light source region
300 and the connection region 320. Here, the light source region
300 and the connection region 320 may be referred to as "conducting
regions" or "conducting parts" for supplying power to the light
source 11.
[0189] That is, the conductive layer 40 may be separated into a
conductive layer 40 of a conducting region for supplying power to
the light source 11 and a conductive layer 40 of a heat dissipation
region for dissipating heat generated from the light source 11.
[0190] The conductive layer 40 of the heat dissipation region 350
is indicated by diagonal lines so as to clearly distinguish the
conductive layer 40 of the conducting region, i.e., the light
source region 300 and the connection region 320 from the conductive
layer 40 of the heat dissipation region 350.
[0191] The heat dissipation region 350 may transfer the heat
generated from the light source 11 to the heat sink 120. Also, the
heat dissipation region 350 may be provided not to be electrically
connected to the light source region 300 and the connection region
320. That is, the heat dissipation region 350 may be provided on a
portion of the insulating layer 20 except the region in which the
light source region 300 and the connection region 320 are provided.
However, the present disclosure is not limited to the
above-described configuration.
[0192] The light source region 300 may include a first light source
mounting part 301 for applying a first electric current to the
light source 11, a second light source mounting part 302 for
applying a second electric current to the light source 11, and a
light source heat dissipation part 303 capable of transferring heat
generated from the light source 11 to the heat sink 120. The light
source heat dissipation part 303 may be provided to be spaced apart
from the first light source mounting part 301 and the second light
source mounting part 302. In addition, a portion of the light
source heat dissipation part 303 contacts the bottom surface of the
light source 11, to transfer the heat generated from the light
source 11, and therefore, the light source heat dissipation part
303 may be referred to as a "contact heat dissipation part."
[0193] The heat dissipation region 350 may include an inner heat
dissipation region 351 provided inside the light source region 330
and the connection region 320, and an outer heat dissipation region
352 provided outside the light source region 300 and the connection
region 320. Here, the conductive layer 40 provided in the inner
heat dissipation region 351 may be referred to as an "internal heat
dissipation part" or "inner heat dissipation part," and the
conductive layer 40 provided in the outer heat dissipation region
352 may be referred to as an "external heat dissipation part" or
"outer heat dissipation part." In addition, the inner heat
dissipation region 351 and the outer heat dissipation region 352
are conductive layers 40 for diffusing heat generated from the
light source 11, and may be referred to as "heat diffusion parts"
or "diffusion heat dissipation part."
[0194] Hereinafter, the inner heat dissipation region 351 is
referred to as an "inner heat dissipation part," and the outer heat
dissipation region 352 is referred to as an "outer heat dissipation
part."
[0195] The inner heat dissipation part 351 and the outer heat
dissipation part 352 may be connected to the light source heat
dissipation part 303. Alternatively, one side and the other side of
the light source heat dissipation part 303 may extend to be
connected to the inner heat dissipation part 351 and the outer heat
dissipation part 352. Here, the light source heat dissipation part
303 may be referred to as a "connection heat dissipation part" for
connecting the inner heat dissipation part 351 and the outer heat
dissipation part 352 to each other.
[0196] That is, the heat dissipation region 350 may be provided
such that the inner heat dissipation part 351, the outer heat
dissipation part 352, and the light source heat dissipation part
303 are integrally formed.
[0197] In another aspect, the heat dissipation region 350 may be
provided such that the inner heat dissipation part 351 and the
outer heat dissipation part 352 are separated from each other.
[0198] Referring to (A) of FIG. 23, the heat dissipation region 350
may be provided such that the inner heat dissipation part 351 and
the light source heat dissipation part 303 are connected to each
other. At this time, the light source heat dissipation part 303
contacts a portion of the light source 11 to conduct heat, and
therefore, may be referred to as a "contact heat conducting part."
In addition, the inner heat dissipation part 351 conducts the heat
conducted from the light source heat dissipation part 303 to the
heat sink 120, and therefore, may be referred to as a "diffusion
heat conducting part."
[0199] According to the above-described configuration, the inner
heat dissipation part 351 may be provided adjacent to the air
guiding part 160 (see FIG. 5). Thus, the heat transferred to the
light source heat dissipation part 303 can be transferred to the
inner heat dissipation part 351. In addition, air flowed into the
air guiding part 160 (see FIG. 5) and the air hole 122 (see FIG. 5)
by the heat transferred through the inner heat dissipation part 351
can be further accelerated. Accordingly, the heat dissipation
efficiency can be improved.
[0200] Referring to (B) of FIG. 23, the heat dissipation region 350
may be provided such that the outer heat dissipation part 352 and
the light source heat dissipation part 303 are connected to each
other. At this time, the light source heat dissipation part 303
contacts a portion of the light source 11 to conduct heat, and
therefore, may be referred to as a "contact heat conducting part."
In addition, the outer heat dissipation part 352 conducts the heat
conducted from the light source heat dissipation part 303 to the
heat sink 120, and therefore, may be referred to as a "diffusion
heat conducting part."
[0201] According to the above-described configuration, the outer
heat dissipation part 352 may be provided as a conductive layer 40
having a relatively wider area than the inner heat dissipation part
351. Thus, the heat transferred from the light source heat
dissipation part 303 can be transferred to the heat sink 120
through the outer heat dissipation part 352 having a wide area.
[0202] That is, the light source heat dissipation part 303 may be
provided to be connected to at least one of the outer heat
dissipation part 352 and the inner heat dissipation part 351. Here,
the inner heat dissipation part 351 and the outer heat dissipation
part 352 may be referred to as a "first diffusion heat conducting
part" and a "second diffusion heat conducting part,"
respectively.
[0203] According to the above-described configuration, the heat
generated from the light source 11 can be more efficiently
transferred to the heat sink 120 by the heat dissipation region
350. In addition, heat is directly transferred from the light
source 11 by the light source heat dissipation part 303, to be
quickly discharged to one of the inner heat dissipation part 351
and the outer heat dissipation part 352.
[0204] FIG. 24 is a perspective view of a lighting device including
light source modules according to an embodiment.
[0205] Referring to FIG. 24, the lighting device 1000 according to
the embodiment may include a main body 1100 providing a space in
which lighting modules 100 are coupled thereto, the main body 1100
forming an external appearance, and a connection part 1200 having a
built-in power source (not shown) coupled to one side of the main
body 1100 to supply power, the connection part 1200 connecting the
main body 1100 to a supporting part (not shown). The lighting
device 1000 according to the embodiment may be installed indoors or
outdoors. For example, the lighting device 1000 according to the
embodiment may be used as a streetlight. The main body 1100 may be
provided with a plurality of frames 1110 capable of providing a
space in which at least two light source modules 100 are
positioned. The connection part 1200 has the power source (not
shown) built therein and connects the main body 1100 to the
supporting part (not shown) fixing the main body 1100 to the
outside.
[0206] If the lighting device 1000 according to the embodiment is
used, heat generated from the light source modules 100 can be
effectively cooled due to a chimney effect. Further, a separate fan
is not used, and thus fabrication cost can be reduced.
[0207] According to the present disclosure, due to effects such as
rapid fabrication processes, inexpensive fabrication cost,
facilitation of mass production, and improvement of product yield,
many advantages can be expected in the production of lighting
devices.
[0208] Particularly, products can be inexpensively fabricated at
high speed. Thus, it is possible to promote the spread of lighting
devices using light emitting diodes.
[0209] Although embodiments have been described with reference to a
number of illustrative embodiments thereof, it should be understood
that numerous other modifications and embodiments can be devised by
those skilled in the art that will fall within the spirit and scope
of the principles of this disclosure. More particularly, various
variations and modifications are possible in the component parts
and/or arrangements of the subject combination arrangement within
the scope of the disclosure, the drawings and the appended claims.
In addition to variations and modifications in the component parts
and/or arrangements, alternative uses will also be apparent to
those skilled in the art.
* * * * *